Apple Cinema Tools 3 - Manual (Page 26)

26 Chapter 1 Before You Begin Your Project
You have the option to use record run or free run timecode during the production:
 With record run timecode, the timecode generator pauses each time you stop
recording. Your tape ends up with continuous timecode, since each time you start
recording it picks up from where it left off.
 With free run timecode, the timecode generator runs continuously. Your tape ends up
with a timecode break each time you start recording.
To avoid potential issues while capturing clips, it is strongly suggested that you use the
record run method, and avoid noncontinuous timecode within a tape.
Whenever a tape has noncontinuous timecode (with jumps in the numbers between
takes), be sure to allow enough time (handles) for the pre-roll and post-roll required
during the capture process when logging your clips. See the Final Cut Pro
documentation for additional information on timecode usage.
About NTSC Timecode
Normal NTSC timecode (referred to as non-drop frame timecode) works as you would
expect—each frame uses the next available number. There are 30 frames per second,
60 seconds per minute, and 60 minutes per hour. Since NTSC’s frame rate at 29.97 fps is
a little less than 30 fps, non-drop frame timecode ends up being slow (by 3 seconds
and 18 frames per hour) when compared to actual elapsed time.
To compensate for this, drop frame timecode skips ahead by two frames each minute,
except those minutes ending in “0.” (Note that it is only the numbers that are
skipped—not the actual video frames.) This correction makes the timecode accurate
with respect to real time, but adds confusion to the process of digital film editing.
With non-drop frame timecode, once you find an A frame, you know that the frame at
that frame number and the one five away from it will always be A frames. For example,
if you find an A frame at 1:23:14:15, you know that all frames ending in “5” and “0” will
be A frames. With drop frame timecode, you are not able to easily establish this sort of
relationship.
Note: It is standard practice to have A frames at non-drop frame timecode numbers
ending in “5” and “0.”
It is highly recommended that you use non-drop frame timecode for both the video
and audio in all film editing projects, even though both Cinema Tools and Final Cut Pro
are able to use either type. Whichever you use, be sure to use the same for both the
video and audio tapes.
Note: PAL timecode does not have this issue—it runs at a true 25 fps.
UP01101.Book Page 26 Thursday, March 10, 2005 3:16 PM